The iontophoresis (Acta Dermatol venereol, vol. 64, p. 93, 1984) and the electropolation (National Patent Publication No. H03-502416, Proc. Acad. Sci. USA, vol. 90, p. 10504 through 10508, 1993) teach a treatment method in which chemicals and physiologically active substance are introduced into a living body from the skin and the mucous membrane by using electric energy. There is also known a method, in which a substance to be diagnosed is extracted from a living body so that the condition of a disease can be observed based on the same principle as above (Nature Medicine, vol. 1, p. 1198 through 1201, 1995). The electrode apparatus is necessarily used in these methods for applying the electric energy to the substances.
Japanese Patent Application Laid-Open No. 2000-316991 discloses an idea in which an electrode apparatus of this type is such designed as to be disposable after use while an external power supply such is designed as to be repeatedly used. The disposable electrode apparatus basically comprises a bending part, a base film including a first and a second part having a difference in height by serving the bending part as a boundary, an electrode layer formed on the base film in such a manner as to cross the bending part and fully extend over the first and second parts which are different in height, and an electrically insulating layer formed on the electrode layer at its selective region including the bending part. An electrode apparatus of this type essentially includes a bending part for the purpose, among others, of defining a receptacle part (dent or recess) for receiving an electrolytic substance on its inner periphery.